Many products are produced in an air or liquid tight manner for environmental, health, freshness, operational and/or other reasons. To meet the need for seal-tight products, test equipment has been developed to test certain types of products for leaks using air tests utilizing micro-flow sensors. For example, U.S. Pat. No. 5,861,546 to Sagi et al., the disclosure of which is expressly incorporated herein by reference, discloses a leak detection apparatus that is suitable for detecting leaks in a product having an opening to which a leak sensor and a vacuum system may be coupled to form a closed test system.
Conventional leak testing systems and methods employ procedures wherein an individual leak test lasts a predetermined amount of time. Each product under test is subjected to the same test time period, regardless of whether the product has a gross leak which is apparent immediately, a marginal leak, an insignificant leak, or no leak at all. Consequently, a given number of products require a relatively fixed period of time for testing.
The present invention provides a method by which the period of time for testing a particular product for leaks is variable and dynamically changes depending upon leak characteristics of the product in the on-going test such as the leakage flowrate and the stability of the leakage flowrate. Thus, it is possible to test a larger number of products in a given period of time as compared to conventional techniques.
These and other features of the present methods and apparatuses will become apparent and be further understood upon reading the detailed description provided below with reference to the following drawings.